/**
 * @Copyright(C) 2008 Software Engineering Laboratory (SELAB), Department of Computer 
 * Science, SUN YAT-SEN UNIVERSITY. All rights reserved.
 **/

package parser;

import exceptions.*;

/**
 * Main program of the expression based calculator ExprEval
 * 
 * @author [PENDING your name]
 * @version 1.00 (Last update: [PENDING the last update])
 */
public class Calculator {
	/**
	 * The main program of the parser. You should substitute the body of this
	 * method with your experiment result.
	 * 
	 * @param expression
	 *            user input to the calculator from GUI.
	 * @return if the expression is well-formed, return the evaluation result of
	 *         it.
	 * @throws ExpressionException
	 *             if the expression has error, a corresponding exception will
	 *             be raised.
	 */
	public double calculate(String expression) throws ExpressionException {
		// You should substitute this method body ...
		double result = ((int) (Math.random() * 1000000000)) / 100.0;
		return result;
	}
}
